The USS San Francisco, a nuclear powered fast attack submarine, was conducting routine operations in the Pacific Ocean when it struck an undersea mountain chain known as the Mariana Trench south of Guam. The collision occurred at high speed, an immediate and unexpected impact that led to catastrophic damage to the submarine’s bow and caused serious injuries among the crew. Tragically, this incident resulted in the death of Seaman Charles E. Dyer, marking a somber moment for the crew and the naval community.

In the aftermath of the collision, the crew exhibited remarkable professionalism and dedication, enabling the submarine to surface despite the damage. The immediate response involved careful assessment of the damage and the implementation of emergency protocols. The USS San Francisco later returned to its home base in Apra Harbor, Guam, where it underwent repairs that would take several months to complete. The Navy initiated a thorough investigation into the circumstances leading to the collision, focusing on navigational practices and potential human error during the mission.

This event prompted a reevaluation of the training protocols for submariners and emphasized the importance of precise navigation techniques when operating under challenging conditions. The findings from the inquiry influenced future submarine operations, leading to enhanced safety measures and a strengthened focus on operational awareness among crews in high-speed maneuvers. The incident underscored the potential dangers of undersea navigation and the critical role of human factors in maritime safety.